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J A WOTTON SAFETY FUSE FOR ELECTRIC GONDUGTORSJ No. 466,761.

Patented Jan. 5, 1892.

UNITED STATES Y PATENT, OFF CE}.

JAMES A. \VOTTON, OF ATLANTA, GEORGIA, ASSIGNOR OF ONE-HALF TO JOHN D. EASTERLIN, OF SAME PLACE.

SAFETY-FUSE FOR ELECTRIC CONDUCTOR S.

SPECIFICATION forming part of Letters Patent No. 466,761, dated January 5, 1892.

Application filed October 12, 1891. $erial No. 408,508. (N model.)

To all whom it may concern:

Be it known that I, JAMES ASHLEY Wor- TON, of Atlanta, in the county of Fulton and State of Georgia, have invented certain new and useful Improvements in Safety-Fuses for Electric Conductors; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to figures of reference marked thereon, which form a part of this specification.

This invention relates, as above stated, to safety-fuses for preventing the passage of a high-tension current to any delicate instrument over a small wire normally carrying a current of a low tension and also to set a limit to the increment of the normal current.

To this end the invention consists in providing a substance having a high electrical resistance and a comparatively low specific heating of said carbon by the passage of the vagrant current, said explosion also serving to blow out or break any are which might form between the two terminals in exceptional cases. I

The invention will be hereinafter fully de scribed, and is shown in the accompanying drawings,in which- Figure 1 is a view of the device, partly in section, showing the carbon with the term-i nals on its end and by the section showing the contents of one of the terminals. Fig. 2 is a like view showing. the explosive within the carbon. Fig. 3 is a cross-section of Fig.

2, further illustrating the elements therein shown.

In the figures like reference-marks indicate corresponding parts in all the views.

1 indicates the wires, and 2 the terminals thereon, 3 being a small stick or piece of carbon or other material possessing high resistance to the passage of the electrical current and a low specific heat. The terminals 2 are preferably of copper and fit over the ends of the carbon 3', while an explosivesuch as gun-cotton, mercury fulminate, or other suitable explosiveis placed within that part of the cap 2 which is not occupied by the carbon. One or both of the terminal-caps 2 may be thus charged. 7

In Figs. 2 and 3 a modification of the device is shown wherein the explosive is placed within the carbon and whereby a heavier explosive discharge may be obtained, which would obviously break a heavier are or highresistance element than would a smaller discharge, and the action of the device would be more certain in its disruptive action. If desired, a fusible wire 4, Fig. 2, having a melting-point slightly higher than the temperature at which the explosion takes place may be incorporated in the inleading wire and should be connected intimately with the cap or terminal to obtain the best results. The heat generated in the carbon or other high-resistance material will be communicated to the caps and melt the fuse-wire in case the explosive does not ignite at its calculated limit.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. In a device of the class specified, a fragile high-resistance element in circuit and an explosive substance associated therewith in such a manner as to be ignited upon the heating of said high-resistance element, for the purpose specified.

2. In a device of the class specified, a fragile high-resistance element in circuit, a metallic cap thereon, and an explosive substance within said cap in the portion not filled by said element, for the purpose specified.

3. In a device of the class specified, the high-resistance element secured at one end to one circuit-wire, a cap containing an ex 4. In a device of the class specified, a me- In testimony whereof I hereunto affix my tallic terminal and a high-fiesistanfce termid signature in presence of two witnesses. nal in contact over part of t eir sur aces an T r v T an explosive substance so arranged between JAMES \X 01 l 5 said terminals as to explode and break the Witnesses: a

circuit upon the heating of the high-resist- A. P. \VOOD, ance terminal, for the purpose specified. A. A. 7001). 

